Usually, circular knitting machines comprise a knitting cylinder having a large number of circumferential needle channels that extend in longitudinal direction of the cylinder. Seated in each of these needle channels are knitting needles, usually latch-type needles. The knitting needles are moved back and forth in the needle channels. This is accomplished with cam assemblies or cam components that are accommodated in cam segments and form the cam housing. This cam housing encloses the needle cylinder and comprises at least one guide path. The knitting needles have feet that run on the guide path and thus impart the knitting needles with the required longitudinal back-and-forth longitudinal movement when the knitting cylinder is being rotated.
Thread is fed to the knitting needles of the rotating knitting cylinder via a thread guide that, as a rule, is stationary. For example, a hose-like knit fabric is formed, said knit fabric hanging from the knitting needles.
In order to prevent the knit fabric from moving up when the knitting needles are driven out, hold-down/knock-over sinkers are usually arranged in the vicinity of the knitting needles. The holding-down/knock-over sinkers involve a not inconsiderable constructional effort. In addition, they require constructional space that can restrict the fineness division in knitting machines.
Document WO 2007/074486 A1 discloses a knitting machine that can operate without holding-down/knock-over sinkers. For this purpose, the knitting needles of the needle cylinder are divided into two groups and are driven by different guide cams of the needle cam assembly. For example, first the even-numbered knitting needles are driven out while the not even-numbered knitting needles arranged in between the are not yet driven out and, as a result of this take over the function of holding down the knit fabric. After the even-numbered knitting needles have been driven out, the odd-numbered knitting needles are driven out, whereupon, finally, the knitting needles are retracted one after the other, i.e., the even-numbered knitting needles as well as the odd-numbered knitting needles, in order to form stitches.
Considering such a knitting machine, the open latches of the knitting needles may abut against other machine elements such as, for example, the thread guide. This may result in a wear of the knitting needles. In addition, the latches of the already driven out knitting needles are to be held in open position at specific locations on their way.